Cover for Molecular Biology and Evolution

Crocheting the mitoribosome – a combination of a hand-drawn illustration with a real structure of the human mitochondrial ribosome.

Ribosomes are giant machineries composed of protein and ribosomal RNA that synthesize proteins encoded by the genome. The genes within mitochondria are synthesized by their own specialized ribosomes – the mitoribosomes, represented by the crocheted structure in the drawing. Unlike other ribosomes, mitoribosomes are highly variable across species, yet the reason for this diversity was previously unknown. To instigate this, a new study examined the composition of mitoribosomes across different species, like humans, flies, yeast, mold, sea urchins, plants and others. A comparison of the structures allowed them to reconstruct the evolutionary history that led to this diversity. Because the RNAs within mitoribosome evolve rapidly, small structural changes lead to instabilities that are patched by introducing other pre-existing structures – the tRNAs. This drawing shows how a tRNA (wrapped around the left hand) is being incorporated into the mitochondrial ribosome by crocheting!

Check out the paper here. Thank you so much Alexey Amunts at Science for Life Laboratory, Stockholm University, Georgia Tech, Harvard Medical School, and Society for Molecular Biology and Evolution!

Combining a drawing with a real protein structure to show how incorporation of tRNA compensates for structural changes during evolution. Molecular Biology and Evolution cover, February 2019.

Combining a drawing with a real protein structure to show how incorporation of tRNA compensates for structural changes during evolution.